Ammunition supply system



Feb. 20, 1951 v. s. KRAEGER ETAL AMMUNITION SUPPLY SYSTEM Filed Feb. 14, 1947 4 Sheets-Sheet l F. r m e Z mm, k yr fiwww rFuMfi MW Z i G w B c Feb. 20, 1951 v; SQKQRAEGER m1. 2,542,200

AMMUNITION SUPPLY SYSTEM Filed Feb. 14, 1947- 4 Sheets-Sheet 2 Feb. 20, 1951 v. s. KRAEGER ETAL AMMUNITION SUPPLY SYSTEM 4 Sheets-Sheet 3 Filed Feb. 14, 1947 l lhcenf 5. Kraeger fir/hal F Pym, .Dec

G'eocge H Hays, fldmr.

Feb. 20, 1951 v. s. KRAEGER ETAL 2,542,200

AMMUNITION SUPPLY SYSTEM Filed Feb. 14, 1947 I 4 Sheets-Sheet 4 Patented Feb. 20, 1951 UNITED STATES TENT OFFICE AMIVIUNITION SUPPLY SYSTEM New Jersey Application February14, 1947, Serial No. 728,630

2 Claims.

This invention relates to ammunition supply systems for aircraft and particularly to a system for maintaining an adequate flow of ammunition to automatic guns mounted in constricted spaces such, for example, as in the tail end of an airin which, plane. Fig. 1 is a vertical section through the tail end A 37 mm. automatic gun, for example, is capa-' of a plane showing a 37 mm. gun and mount and ble of firing at a rate as high as 120 rounds a the positions of a gunner and the end portion of minute and obviously the quantity of ammunition an ammunition round transferer relative which may be required in a short time under thereto; combat conditions will occupy more space than Fig. 2 is a perspective view of the end portion is available at a gun station in a turret or the of the ammunition round transferer, enlarged to tail of an airplane. It is the object of the present; illustrate switch operating mechanism for coninvention to provide for the automatic delivery, trolling operation of the transferer; to the constricted space adjacent to the gun at Fig. 3 is a perspective view of the supply magasuch a station, of a continuous supply of ammuni; zine midway of the plane and the rear portion of tion at any rate at which it might be needed. With the thansferer tube; this in view the invention provides a power driven Fig. 4 is a section on the line IV-IV of Fig. 3 round transferer which is automatically respond Fig. 5 is an elevation near the top of the supply sive to the presence or absence of a round of magazine as seen from the right side of Fig. 3 ammunition at the gun station to transfer indimostly in the plane of the forward one of the vidual rounds successively from a large source endless chains, showing the endless chain and of supply, such as a magazine in the mid-portion clips which support the base ends of the rounds of an aircraft where there is sufiicient room for of ammunition and the bracket which supports ammunition storage, to a delivery position in the the forward end of the transferer tube; constricted pace at a gun Station, so that when- Fig. 6 is a side view, partly in section, illustratever the gunner picks up a round to insert it in a ing the constructional features of the ammunicartridge feeder upon the gun, another round tion round clip and its attachment to the endless immediately takes its place and, consequently, chain; there is always a round at hand ready for use, Fig. '7 is a pe p t e f the p r p even though there is no space available at the ated means for driving the magazine and the gun station for storage of a reserve supply. In transferer chains; and 1 the illustrated embodiment of the invention the Fig 8 is a diagrammatic layout of the electrical ammunition magazine which constitutes a large circuit for controlling the power operated means. source of supply consists of an upright endless Referring to the drawings, Fig. 1 shows averticarrier located in the mid-portion of an aircraft cal section through the tail portion IU of an airwhere there is ample room. A round transferer plane in which there is mounted, on a suitable extends from the upper end of the magazine trunnioned support I2, a 37 mm. automatic gun rearward along the ceiling of the fuselage to a M which may be operated by a gunner l6 stand delivery position in the constricted space at the 40 ing on the floor 18 at the rear of the gun. The "a gun station in the tail of the aircraft. The endgun is provided with the usual feed magazine 20 less carrier and the transferer are normally both which holds a sufficient number of rounds of ammoved intermittently, each moving during munition for several short bursts of fire. The periods when the other is at rest and both be-.' magazine 20 is replenished with ammunition by i step Whenever there is a round of a the gunner at intervals between bursts of fire, munition in e delivered p on t e un while the gun is cooling. Because of the rather station, where the delivered round, if it is not reconstricted space available in the tail portion of 0 moved by the gunner, engages and holds open a the plane and because the gun uses a large quan Switch Controlling the Power p y Circuit of an tity of ammunition, it is not feasible to store an electric motor by which the mechanisms are opadequate supply of ammunition in the v c ty of erated- AS ee as e gunner p s up the the gun. Hence, the present invention provides round to place it in the cartridge feeder on the for transferring ammunition from a remote gun the switch closes, the motor starts, and anpoint, for example, in the midportion of the airother round .is delivered immediately to the gun plane, where there is ample space for storing am-. station so that the gunner may replenish the o munition, to the gunner in the constricted space,

cartridge feeder as fast as it is emptied,

The features and details of the invention will be readily understood from the following description of one embodiment thereof when read in connection with the accompanying drawings in a convenient position for him to receive it one a ground at a time for insertion in the feed magazine 20. As indicated in Fig. l, a rear end at- Qtachment. 2 4 to an ammunition transfer tube 22 he may readily grasp a round of ammunition A delivered to the attachment 24 without having to look away from his target. The ammunition transfer tube 22 extends from theattachment 24 at the tail, or any constricted portion, of the airplane, upward along the ceiling of the plane to a supply magazine indicated generally at 26 (Fig. 3) located in the midportion of the plane. The magazine 26 consists of a pair of parallel spaced endless chains 28, inclined slightly from the vertical, mounted upon pairs of sprockets 38 and 32 (Figs. 3 and The sprockets 3d, 36 are fixed to a shaft 34 which is journaled in a horizontal position in bearings 35 formed integral with spaced upright posts 58 fixed at their lower ends to a base plate 40, the latter being in turn fastened to the floor 42 of the airplane in the midportion thereof. The upper pair of sprockets 32, 32 are fixed to a horizontal shaft 44 parallel to the shaft as (Figs. 5 and 7), this shaft being supported from the ceiling 46 of the airplane in suitable bearings, not shown herein, and being. driven to impart linear movement to the chains 28-intermittently as will appear hereinafter.

Secured to thechains 28 are ammunition round carriers 48 (Fig. 5), the carriers being, fixed to alternate links 58 of the chains 28 and extending transversely between the chains. Each carrier consists of rear and forward pairs of curved finand 6) adapted to engage the rear side of the" flange I8 to lock it against the cross-portion 60. The finger I2 is formed integral with an arm I4 and projects upwardly therefrom through an opening 16' formed in the link 58. The arm I4 is pivoted on a pin 80 supported between ears 82 fixed to the under side of the strap 62. A torsion spring 86 surrounding the pin 80 and bearing at one'end against the strap 52 and at its votherend against the .arm I4 yieldably urges the arm in a direction to cause the finger I2 to profeet through the opening I6 into engagement with the flange I8. The arm I4 is guided in its movement by slots 34 formed in the under side of the link 50 with which it is associated. The arm 74 is also provided with a laterally extending portion 88' which projects beyond the link 50 of the chain and provides means, which will be described, for withdrawing the finger I2 at gers 52 and 54 (Figs. 3 and 5.), longitudinally spaced to embrace respectively the nose and base of, a round of ammunition. The forward and rear fingers at each side of the carrier are joined by a strap 56 (Figs. 3 and 6) which is welded at one end: to one of'the rear fingers 52 at 58, extends forward to the forward fingers 54 on the same side, to which it is welded, then crosswise be the proper time from behind the flange l8 to reelectric motor 92 (Figs. 3 and 7).

shown in phantom at 98 (Fig. 5), which is supported at its forward end by a casting 93 formed at the lower end of a depending bracket94 se-. cured to the ceiling of the airplane.

fer tube 22 is a hollow substantially cylindrical member (Fig. 4:) of sufficient inside. diameter... to accommodate the ammunition and is supported from the ceiling of the airplane at spaced points throughout its length, the supports being of a conventional type and not illustrated herein. The forward end of the transfer tube is supported by the casting es in alinement with the normal stopping position of one of the ammunitween the forward fingers 54, being welded to the'oppo'site one of the forward fingers 54 and finally rearward to the opposite rear finger 52,

to which it is welded. The cross-portion, designated 60, of the strap forms an abutment against which the base flange I8 of the round of ammunition A abuts and is held, as will appear hereinafter. For supporting the under side of the round of ammunition and also for maintaining the spacing between the chains 28, corresponding opposite links in the chains 28 are riveted to the opposite ends of a strap 62 disposed be tween them. The links 5!! of each chain are joined by intermediate links 64 (Fig. 5) to which they are pivoted by pins 66 and the chains are? project into the channel-shaped members I58.

In order to hold each round of ammunition A securely in its carrier 48 so that it will not slip out; even during the most violent gyrations of the airplane, each of the links 50 of the chain 28 is provided adjacent to the base of the round of ammunition with a locking finger 12 (Figs. 5

tion carriers 48 on the chains 28 near the top thereof so that if a round of ammunition is pushed lengthwise from its carrier, it will enter the forward end of the transfer tube 22. To accomplish this, there is provided an endless chain I 62 which is driven by a sprocket I5d (Fig- 3) and passes around an idle sprocket I22 at the 5 The chain I Miss.

rear end of the transfer tube. so disposed that one of its runs lies close to the carrier opposite the forward end of the tube 22 That portion of the chain which travels length; wise of the carrier is guided and supported in its movement by a channel member I03 fixed at one end to the casting 98 and at its other end to an outstanding bracket I05 formed integral with a gear housing I57. An idle sprocket III mounted on a pin between ears. i I3 formed at one end of. the channel member I63 overlies the chain, directing it into the channel member I83 and holding it therein. At spaced intervals along the-.

chain' I02, specifically at distances equal to the length of a round of ammunition, there are fixed fingers I04 each of which, as the chain moves through into the transfer tube and to move the r The tranS-.

entire length of the tube, to push a round of ammunition from one end to the other. The other run of the chain is supported by a housing I05 (Figs. 3 and 4) which is secured paral'el to the transfer tube 22 between the casting 96 and a casting at the rear end of the transfer tube to be hereinafter described. Openings I01 are formed in the casting 96 through which the runs of the chain I02 may pass forward from the forward ends of the housings I and I05 to the sprocket I54.

In order to release a round of ammunition from its carrier 48, there is provided a stationary wedge-shaped member I 06 (Figs. 5 and 6), secured by a bracket I09 (Fig. 6), to which it is bolted,

to the channel-shaped guide 66 adjacent to the n base of the ammunition in a position to be engaged by the inside of the end portion 88 of the arm 14 (Fig. 6) to withdraw the finger 12 simultaneously with the movement of the carrier into a position opposite the forward end of the transfer tube 22.

Referring now to the attachment 24 at the rear end of the transfer tube 22, there is shown in Fig. 2 a casting I 08 having spaced circular arms I I0 adapted to embrace the rear end portion of the tube 22. This casting also has spaced overhanging arms II2 to which the rear end of the chain housing I05 is fastened, the latter being secured between the casting and the overhanging arms II2 by plates II6. Secured to one side of the casting is a plate II1 which is adapted to be fastened to the wall of the airplane or some other supporting member fixed in the tail portion of the plane to hold the casting at the proper heightwise position as heretofore mentioned. The plate H1 is provided with a bearing sleeve I I8 (Fig. 3) in which there is journaled a stub shaft I to which there is fixed a sprocket I22 (Fig. 2) over which the chain I02 passes. A chain guard I24 extends around the chain and the s rocket and is secured to the plate H1 at I26. There are also secured to the plate H1, in alinement with the rear end portion of the transfer tube 22, pairs of spaced concave resilient fingers I28 adapted to receive and embrace the nose and base of a round of ammunition A as it is delivered from the end of the tube.

In order to prevent the feeding of further ammunition to the fingers I28 when they already contain around, means is provided for automatically stopping the driving motor if the gunner does not remove the round from the fingers. This means comprises a hook-shaped member I30 (Fig. 2) which projects upward into the path of the round adjacent to the end of the transfer tube from one end of a slide I3I reciprocable in ways I32 (Fig. 3) cut in the base I34 of the cast-- ing I08. The slide I3I is provided with a downwardly projecting finger I36 which is adapted to engage, when the slide has been moved rearward by a round engaging the hook I30, the upwardly inclined end of an arm I38 pivoted on a pin I48 and to push the arm down into engagement with a switch button I44 of a switch I46, to hold an operating circuit (to be described hereafter) of the motor 92 open so that the driving mechanism 90 will be at rest. The arm I38 is yieldably held out of contact with the switch button I44 by a spring I42 and will only be depressed by movement of the slide I3I to a rearward position, as indicated in the drawings. The slide I3I is normally urged forward by a spring I and will take up aposition against an adjustable stop I56 when there is no ammunition present in the fingers I28.

When such a condition exists the aforementioned circuit is automatically closed to start the motor and, hence, to cause the chain I02 to deliver another round of ammunition from the end of the transfer tube into the fingers in a position to be picked up by the gunner.

- Returning now to the magazine end of the apparatus, the means for rotating the sprocket I54 to drive the chain I02 and also the means for rotating the sprockets 32 to drive the chains 28 will now be described.

The sprocket I54 (Fig. 7) is fixed to a shaft I55 journaled in one wall of the gear box I51 (Fig. 3) and is connected by a clutch I56 to one end of a horizontal shaft I58 also journaled in suitable hearings in the gear box as are all the other "shafts hereinafter to be mentioned. The shaft I58 has fixed to it at its opposite end a helical gear I 60. The gear I60 meshes with a helical gear I62 splined for longitudinal movement on a shaft I64 to which is fixed a gear I66 meshing with a gear I66 fixed to a parallel shaft I 10. A worm gear I12 fixed to the shaft I10 meshes with a worm I14 fixed to the motor shaft I16. When the motor 92 is operating, power will be transmitted to the sprocket I54 to drive the chain I02 through the described gear train. It is necessary that the chain I62 shall operate intermittently in timed relation to similar intermittent movement of the chains 28 of the magazine, in such a way that the chain I62 will be stationary while the chains 28 are moving a round of ammunition into alinement with the forward end of the transfer tube 22 and thereafter the chain I02 will move to transfer the round into the tube while the chains 28 are stationary. To this end there is fixed to one end of the gear I62 (Fig. '7) a hub I16 which is slidable axially with the gear I 62 on the shaft I64. The hub has a cam groove I19 in its peri heral surface adapted to embrace a fixed pin I so that as the hub rotates with the gear I62 the groove will, because of its design, either impart axial movement to the gear I62 in such a direction and at such a rate that rotational movement will be transmitted from the motor 92 to the sprocket I54, thereby imparting linear movement to the chain I02 through a distance sufficient to move one round of ammunition from its carrier on the chains 28 into the transfer tube 22, or impart longitudinal movement to the gear I62 in the opposite direction at such a rate with respect to the gear I60 that no.

is moved, so that the chains 28 will advance a distance equal to the distance between the ammunition carriers, to move one round of ammunition at a time into alinement with the transfer tube 22 and then to remain at rest until the chain I02 removes the round from its carrier and pushes it into the transfer tube. To this end there is fixed to the shaft 44 a gear I 82 which meshes with a worm I84 splined for longitudinal movement on a shaft I86. Fixed to one end of the shaft I86 is a gear I88 which in turn meshes with a gear I90 fixed to the shaft I 10. To provide the necessary intermittent motion there is fixed to the worm I84 a hub I92, the peripheral surface of which has a cam groove I93 amazed therein embracing a fixed pin. I94: This mechanism. operates in exactlytho same way as the mechanism for driving the chain I02, and, hence, the description of its operation need not be re peated herein. Ihe design of the cam groove is somewhat different from that of the groove- !19 because of the fact that the chains 28 move a shorter distance than does the chain I02.

The motor 92 and the power transmitting mech- V anism 90, which includes the gearing described above, for operating the chains 28 and I02 are controlled by a. system of switches illustrated in a circuit shown diagrammatically at I96 in Fig. 8.

'As shown therein the motor 92 is grounded at I98. A source of electrical power indicated at 202 may be connected to the circuit I96 by a manually operated main switch 29!! (Figs. 2 and 8). initially, when the transfer tube. contains no ammunition, the switch M6 is in a closed position by reason of the absence of a round of ammunition from the fingers I28 as heretofore explained, this switch, as will be seen by reference to the circuit diagram, being in series with a loading switch 228 by way of a conductor 224 and with the main switch 293 by way of a conductor 222. Hence by closing the loading switch 220 (Figs. 2 and 8) current may pass from the conductor 202 through the switch 200, the conductor 222, switch 220, conductor 224 and switch I46 to a conductor 228 which is connected to a solenoid 208. The solenoid is grounded at 2I2 by a conductor 2H3 connected to the solenoid coil and has a plunger 2M arranged to bridge, when actuated by excitation of the coil, spaced terminals 2H5 in a conductor 2&8 leading from the switch 25s to the motor 92. Thus the motor will start and the magazine chains 28, and the transfer chain M2, will be operated as heretofore described. As soon as the first round of ammunition reaches the rear end of the transfer tube 22 and is delivered into the fingers I28, the switch 2% will be opened, interrupting the current to the solenoid 268, with the result that the plunger 2M will be retracted, the current to the 'motor will be interrupted and the 'motor will stop. Hence movement of the magazine loading chains 28 and the transfer chain I62 will cease. At any time when the carriers on the magazine chains 28 may not be filled withammunition and it is desired to complete the filling thereof without operating the transfer chain I02, the clutch I56 may be disengaged to disconnect the sprocket I54 from the shaft I58. Disengagement of the clutch operates by contact of its handle with a normally open switch 2'26.

to close the switch, permitting current to pass from the switch 23!! through aconductor 2%, the switch 225 and a conductor 28% to the solenoid coil 2B8, closing the gap between the terminals 2H3 in the conductor 2 I8 and starting the motor 92. The motor will now operate the loading chains 28 without operating the transfer chain, so that the magazine may be completely filled. As soon as it is filled the clutch is disengaged, permitting the switch 226 to open and stop the motor, whereupon the apparatus is in readiness for use.

From the description of the apparatus outlined above, it is evident that it provides convenient means for supplying a large number of rounds of ammunition to a constricted portion of a plane where it is impossible to store sufficient ammuni- 8. tion'.to-keep.a rapid firing gun'supplied' atolltimes. p r

In order to prepare the apparatus: for. opera:- tion', the main switch 20% (Fig. 8) is first closed, and then if the apparatu is entirely empty of; ammunition, the loading switch 220 is closed; whereupon the magazine chains 28 will begin: their intermittent movement as will also the;- transfer chain [82. The loader will then dur-. ing periods of rest of the chains 28 place ammunition in the ammunition carriers 48. As the chains 28 move a round of ammunition into position in alinement with the transfer tube 22,- the transfer chain I62 will transfer the ammunition, a round at a time, into the transfer tube, 22 until the transfer tube is filled, whereupon, the operation of" the device will be interrupted-I by the first round of ammunition reaching the terminal portion of the transfer tube and enters ing the fingers E23 so as to open the switch'l' liir At this time the carriers 43 will not necessarily: all be filled with ammunition. Hence, in order that the magazine 2% may be completely filled up, the loader will then disengage the clutch I5 5 so that the transfer chain Hi2 will no longer move which simultaneously closes the switch 226 and, keeping the switch 225 closed, will continue to insert rounds of ammunition in the ammunition carriers 48 as the chains 28' continue their intermittent movement. When the carriers on these magazine chains have been filled with ammunition, the operator will reengage the clutch, whereupon the mechanism will come to a stop and will remain thus in readiness for use untila round of ammunition is removed from the fingers I28. At this time the switch 2&9 may also be opened so that there will be no chance that the mechanism will be accidentally started by unauthorized removal of a round of ammunition from the fingers lZt. When the gunner is ready for firing, he will close the switches 25.") and 220 so that the mechanism will be in readiness to operate automatically upon removal of around of ammunition from the fingers I28.

As soon as the gunner removes the round of ammunition at the rear end of the transfer tube from the fingers I28, the switch M6 is automatically closed, the motor 92 is started, the trans--' fer chain I02 moves lengthwise of the transfer tube a distance sufficient to move the round of ammunition in the carrier opposite the forward" end of the transfer tube into the tube and simultaneously moves the round of ammunition in the" rear end of the tube into the fingers I28 in readiness to be grasped by the gunner. Then the chain I02 comes to a stop and the magazine chains 28 move upward a distance suiiicient' to" move the next round of ammunition into ali'ne'-"-' ment with the forward end of the transfer tube and come to a stop. The chain 552 now starts and, if the gunner has not removed the round" previously deposited in the fingers 128, the rim of that round, engaging the hook I30, will move the slide I3I rearward, causing the switch I46 to be opened to stop the motor, and the entire mechanism will come to a stop and remain at rest. However, if the gunner has removed that round of ammunition, the mechanism will con tinue to operate as previously described.

Having thus described this invention, what is claimed as new and desired to be secured by Letters Patent of the United States is:

'1. In an ammunition supply system, the combination of an ammunition magazine comprising an endless carrier having a series of manually loadable holders for individual rounds of ammunition, an electric motor, a power supply circuit for the motor, intermittent driving mechanism connecting the motor to the carrier, round transferring apparatus extending from said magazine to a remote delivery station, intermittent driving mechanism including a clutch connecting said motor to the transferring apparatus, a normally open switch in the motor power supply circuit, clutch disengagin means, and means responsive to movement of the clutch disengaging means for closing the switch to start the motor.

2. In an ammunition supply system, an ammunition magazine comprising an upright, motor driven, endless conveyor having a series of manually loadable holders for individual rounds of ammunition, a round transferer extending from the top of said magazine to a remote gun station, a round receiver at said station, a normally closed switch in the power supply circuit of the motor, a switch opener adjacent to the round receiver in position to be engaged by a round upon the receiver, to open said switch, and a separate, normally open, switch in the power supply circuit of the motor operable to supply power to the 9 motor independently of the first-named switch. VINCENT S. KRAEGER. GEORGE H. HEYS,

Administrator of the Estate of Arthur F. Pym,

Deceased.

10 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 683,039 Hagen Sept. 24, 1901 1,355,488 McKenney Oct. 12, 1920 2,148,262 Doe Feb. 21, 1939 2,382,522 Trotter Aug. 14, 1945 2,402,777 Rose et al June 25, 1946 2,403,170 Chapman et a1. July 2, 1946 2,407,692 Vickers Sept. 17, 1946 2,428,414 Elliott Oct. 7, 1947 2,429,497 Trotter Oct. 21, 1947 OTHER REFERENCES Aviation, March 1945, page 140. Martin Publication: Ammunition Booster Units, Recd. Dec. 12, 1945. 

